store_list_expensive_books_prefetch_related_efficient.py

@query_debugger
def store_list_expensive_books_prefetch_related_efficient():

    queryset = Store.objects.prefetch_related(
        Prefetch('books', queryset=Book.objects.filter(price__range=(250, 300))))

    stores = []
    for store in queryset:
        books = [book.name for book in store.books.all()]
        stores.append({'id': store.id, 'name': store.name, 'books': books})

    return stores